Synthesis and characterization of hydroxyapatite/Ca-zirconia nanoparticle composites

0450427 - ÚFM 2016 RIV ES eng A - Abstract
Částková, K. - Hadraba, Hynek - Roupcová, P. - Matoušek, A. - Cihlář, J.
Synthesis and characterization of hydroxyapatite/Ca-zirconia nanoparticle composites.
14th International Conference European Ceramics Society. Toledo: ECERS, 2015. ISBN 978-84-606-9257-7.
[ECERS 14 - International Conference of the European Ceramic Society /14./. 21.06.2015-25.06.2015, Toledo]
R&D Projects: GA MŠMT(CZ) ED1.1.00/02.0068
Institutional support: RVO:68081723
Keywords : hydroxyapatite * zirconia * composite
Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

Ceramic materials are widely used for bone tissue repair, however, it is still hard to rebuild tissue with its original morphology and physical properties. The main effort of researchers is to develop biomaterials with mechanical properties and biocompatibility appropriate to the bone repair. The aim of the work is to prepare HA/ZrO2 nanoparticles and composites with microporous structure and to study the effect of calcium oxide (as a zirconia dopant) on the phase composition, mechanical properties and bioactivity of the composites. HA nanoparticles were prepared by precipitation synthesis at 20 and 80°C and by hydrothermal posttreatment. Ca-ZrO2, rep. Y-ZrO2 nanoparticles were synthesized by sol-gel precipitation. HA/CaZrO2 and HA/Y-ZrO2 composites were prepared by mixing of HA and ZrO2 nanoparticles in different weight ratio. The particle mixtures were uniaxially pressed into discs and sintered. The particles and composites were characterized by means of XRD, SEM, TEM and BET. Biological activity of HA/ZrO2 composites was studied by means of interaction with simulated body fluid and cell adhesion of the human osteosarcoma cell line MG63. Vickers hardness and the indentation modulus of elasticity of the composites were determined by means of instrumented hardness tester (according to the EN ISO 6507 standard. Nanoparticle composites with microporous structure and with grain size up to 10mm and density 99%TD were prepared by milling, uniaxial pressing and sintering at 1200°C. Due to diffusion of Ca ions from HA to ZrO2 the phase transformations took place in the composites during sintering. HA was decomposed into a mixture of HA and calcium phosphates and simultaneously the new phase- calcium zirconate was formed. The lower concentration gradient of calcium between phases partially inhibited the HA decomposition in Ca-ZrO2/HA composites. Ca-ZrO2/HA composites showed higher bioactivity by SBF testing than these of Y-ZrO2/HA.
Permanent Link: http://hdl.handle.net/11104/0252505